- Research Article
- 10.3114/sim2025.112.02
- Sep 30, 2025
- Studies in Mycology
- B.s Weir + 22 more
Facial eczema (FE) in ruminants is associated with the fungal toxin sporidesmin that can cause significant mortality in grazing livestock. Incidences are particularly severe in New Zealand but are reported worldwide. The syndrome has historically been attributed to Pithomyces chartarum , a species transferred to Pseudopithomyces Pithomyces taxonomy of Pseudopithomyces concatenated protein coding genes distinguished 15 species in the genus. We describe Pseudopithomyces toxicarius sp. nov. as a novel sporidesmin Pse. chartarum , with 80 % of isolates in this study able to produce the toxin. Two Pithomyces species are combined into Pseudopithomyces as Pseudopithomyces cynodontis comb. nov . and Pseudopithomyces pavgii comb. nov . We also place Pseudopithomyces pandanicola in synonymy with Pseudopithomyces palmicola. Pithomyces terricola Longipedicellataceae as Pseudoxylomyces terricola comb. nov . Pseudopithomyces chartarum was the only other species where sporidesmin was detected, but this was found in only one of 14 isolates we tested. The extent of sporidesmin synthesis in this genus remains to be determined due to the limited availability of strains for testing in other species. Pse. toxicarius , Pse. chartarum and Pse. palmicola revealed distinct genetic subclades within each species. Four species were detected in New Zealand. Pseudopithomyces toxicarius and Pse. chartarum Pse. palmicola Pseudopithomyces suggesting widespread global distribution.
- Research Article
- 10.3114/sim.2025.111.0330
- Jun 15, 2025
- Studies in Mycology
- J.l Nybo + 36 more
The genus Aspergillus is diverse, including species of industrial importance, human pathogens, plant pests, and model organisms. Aspergillus includes species from sections Usti and Cavernicolus, which until recently were joined in section Usti, but have now been proposed to be non-monophyletic and were split by section Nidulantes, Aenei and Raperi. To learn more about these sections, we have sequenced the genomes of 13 Aspergillus species from section Cavernicolus (A. cavernicola, A. californicus, and A. egyptiacus), section Usti (A. carlsbadensis, A. germanicus, A. granulosus, A. heterothallicus, A. insuetus, A. keveii, A. lucknowensis, A. pseudodeflectus and A. pseudoustus), and section Nidulantes (A. quadrilineatus, previously A. tetrazonus). We compared these genomes with 16 additional species from Aspergillus to explore their genetic diversity, based on their genome content, repeat-induced point mutations (RIPs), transposable elements, carbohydrate-active enzyme (CAZyme) profile, growth on plant polysaccharides, and secondary metabolite gene clusters (SMGCs). All analyses support the split of section Usti and provide additional insights: Analyses of genes found only in single species show that these constitute genes which appear to be involved in adaptation to new carbon sources, regulation to fit new niches, and bioactive compounds for competitive advantages, suggesting that these support species differentiation in Aspergillus species. Sections Usti and Cavernicolus have mainly unique SMGCs. Section Usti contains very large and information-rich genomes, an expansion partially driven by CAZymes, as section Usti contains the most CAZyme-rich species seen in genus Aspergillus. Section Usti is clearly an underutilized source of plant biomass degraders and shows great potential as industrial enzyme producers.
- Research Article
- 10.3114/sim.2025.111.02
- Jun 15, 2025
- Studies in mycology
- W M Jaklitsch + 4 more
The genus Camarosporidiella is here assessed with respect to its phylogenetic structure and species composition. More than 160 pure cultures from ascospores and conidia of more than 150 fresh collections, mostly from Fabaceae, were prepared as DNA sources. Molecular phylogenetic analyses of a multigene matrix of partial nuSSU-, complete ITS, partial LSU rDNA, and tef1 exon sequences of our isolates and those of previous workers revealed that these markers are insufficient to provide a complete species resolution. From this reduced data matrix, however, we propose synonyms and accept taxa for previously described species, which could not be included in the final phylogenetic tree due to lack of rpb2, tef1 intron and tub2 sequences. The final phylogenetic tree, which was inferred from a combined nuSSU-ITS-LSU-rpb2-tef1-tub2 sequence matrix resolved our isolates into 27 statistically supported phylogenetic species, of which 15 are new. Altogether 34 species are here accepted in Camarosporidiella. Using type studies we stabilise old names, lectotypify Cucurbitaria asparagi, Cucurbitaria caraganae, Cucurbitaria coluteae, Cucurbitaria euonymi, Dichomera elaeagni Hendersonia mori, Sphaeria elongata, Sphaeria laburni Sphaeria spartii and epitypify them as well as Cucurbitaria cytisi, Cucurbitaria retamae and Cucurbitaria steineri to place them in their correct phylogenetic positions and fix their taxonomic concepts. Morphology alone is not suitable to identify these species, and therefore no determinative key to species can be given. However, if hosts are reliably identified, many species can be determined without molecular data. Host images are included with the figures of each fungal species. Taxonomic novelties: New species: Camarosporidiella aceris Jaklitsch & Voglmayr, Camarosporidiella aetnensis Jaklitsch & Voglmayr, Camarosporidiella aragonensis Jaklitsch & Voglmayr, Camarosporidiella asparagicola Jaklitsch & Voglmayr, Camarosporidiella astragalicola Jaklitsch & Voglmayr, Camarosporidiella cretica Jaklitsch & Voglmayr, Camarosporidiella echinosparti Jaklitsch & Voglmayr, Camarosporidiella hesperolaburni Jaklitsch & Voglmayr, Camarosporidiella longipedis Jaklitsch & Voglmayr, Camarosporidiella maroccana Jaklitsch & Voglmayr, Camarosporidiella ononidis Jaklitsch & Voglmayr, Camarosporidiella radiatae Jaklitsch & Voglmayr, Camarosporidiella spartioidis Jaklitsch & Voglmayr, Camarosporidiella sphaerocarpae Jaklitsch & Voglmayr, Camarosporidiella tridentatae Jaklitsch & Voglmayr. New combinations: Camarosporidiella asparagi (Maire) Jaklitsch & Voglmayr, Camarosporidiella caraganae (P. Karst.) Jaklitsch & Voglmayr, Camarosporidiella coluteae (Rabenh.) Jaklitsch & Voglmayr, Camarosporidiella cytisi (Mirza) Jaklitsch & Voglmayr, Camarosporidiella elaeagni (P. Karst.) Jaklitsch & Voglmayr, Camarosporidiella euonymi (Cooke) Jaklitsch & Voglmayr, Camarosporidiella retamae (Pat.) Jaklitsch & Voglmayr, Camarosporidiella steineri (Petr.) Jaklitsch & Voglmayr. New names: Camarosporidiella neomori Jaklitsch & Voglmayr, Camarosporidiella neospartii Jaklitsch & Voglmayr. Citation: Jaklitsch WM, Blanco MN, Rejos FJ, Tello S, Voglmayr H (2025). Camarosporidiella, a challenge. Studies in Mycology 111: 19-100. doi: 10.3114/sim.2025.111.02.
- Research Article
1
- 10.3114/sim.2025.111.01
- Jun 15, 2025
- Studies in mycology
- R Franco-Duarte + 5 more
The winemaking industry faces unprecedented challenges due to climate change and market shifts, with profound commercial and socioeconomic repercussions. In response, non-Saccharomyces yeasts have gained attention for their potential to both mitigate these challenges and enhance the complexity of winemaking. This study builds upon our previous cataloguing of 293 non-Saccharomyces yeast species associated with winemaking environments by rigorously analysing 661 publicly available genomes. By employing a bioinformatics pipeline with stringent quality control checkpoints, we annotated and evaluated these genomes, culminating in a robust dataset of 530 non-Saccharomyces proteomes, belonging to 134 species, accessible to the research community. Employing this dataset, we conducted a comparative phylogenomic analysis to decipher metabolic networks related to fermentation capacity and flavor/aroma modulation. Our functional annotation has uncovered distinctive metabolic traits of non-Saccharomyces yeasts, elucidating their unique contributions to enology. Crucially, this work pioneers the identification of a non-Saccharomyces 'fermentome', a specific set of six genes uniquely present in fermentative species and absent in non-fermentative ones, and an expanded set of 35 genes constituting the complete fermentome. Moreover, we delineated a 'flavorome' by examining 96 genes across 19 metabolic categories implicated in wine aroma and flavour enhancement. These discoveries provide valuable genomic insights, offering new avenues for innovative winemaking practices and research. Citation: Franco-Duarte R, Fernandes T, Sousa MJ, Sampaio P, Rito T, Soares P (2025). Phylogenomics and functional annotation of 530 non-Saccharomyces yeasts from winemaking environments reveals their fermentome and flavorome. Studies in Mycology 111: 1-17. doi: 10.3114/sim.2025.111.01.
- Research Article
1
- 10.3114/sim.2025.111.04
- Jun 15, 2025
- Studies in mycology
- L Zhao + 4 more
The ascomycete family Bionectriaceae (Hypocreales) contains cosmopolitan species distributed throughout a broad range of environments, mainly occurring in terrestrial and freshwater ecosystems, with a less frequent occurrence in marine habitats. Members of the family are commonly used in industrial, pharmaceutical, and commercial applications. Applications utilise biodegraders and biocontrol agents, while certain taxa serve as a rich source of bioactive secondary metabolites. In recent years, several studies have proposed new taxonomic concepts within Bionectriaceae based on multi-gene phylogenetic inference. However, the status of several genera remains controversial or unclear, and many need to be re-collected and subjected to molecular analysis. The present study aims to improve our understanding of Bionectriaceae by re-examining CBS culture collection strains preliminarily identified as taxa within this family. Morphological and molecular phylogenetic analyses are based on alignments of the nuclear ribosomal subunits consisting of the internal transcribed spacer regions and intervening 5.8S nrDNA (ITS), as well as partial sequences for the 28S large subunit (LSU) nrDNA. Additional regions within protein-encoding genes were used, including the DNA-directed RNA polymerase II second largest subunit (RPB2), and translation elongation factor 1-alpha (TEF1) regions. The sequences generated were used to reconstruct a phylogenetic backbone of the family Bionectriaceae, and to delineate lineages and generic boundaries within it. Based on these results, seven new genera, 35 new species, and nine new combinations are proposed. A robustly supported phylogenetic framework is provided for Bionectriaceae, resolving 352 species and 50 well-supported genera. This study provides a solid foundation for more in-depth future studies on taxa in the family. Taxonomic novelties: New genera: Clavatomyces Lin Zhao & Crous, Collarimyces Lin Zhao & Crous, Vitreipilata Lin Zhao & Crous, Parageonectria Lin Zhao & Crous, Physaromyces Lin Zhao & Crous, Smyrniomyces Lin Zhao & Crous, Urticomyces Lin Zhao & Crous. New species: Acremonium paramultiramosum Lin Zhao & Crous, Clavatomyces prestoeae Lin Zhao & Crous, Clonostachys novocaledonica Lin Zhao & Crous, Clonostachys tropica Lin Zhao & Crous, Collarimyces guttiformis Lin Zhao & Crous, Emericellopsis mexicana Lin Zhao & Crous, Emericellopsis proliferata Lin Zhao & Crous, Emericellopsis soli Lin Zhao & Crous, Fusariella triangulispora Lin Zhao & Crous, Geonectria alni Lin Zhao & Crous, Geonectria quercus Lin Zhao & Crous, Geosmithia cupressina V. Meshram et al., Geosmithia magnispora Lin Zhao & Crous, Gliomastix olivacea Lin Zhao & Crous, Hydropisphaera armeniaca Lin Zhao & Crous, Hydropisphaera gossypina Lin Zhao & Crous, Hydropisphaera martinicensis Lin Zhao & Crous, Hydropisphaera solani Lin Zhao, L.W. Hou & Crous, Lasionectria chondroidea Lin Zhao & Crous, Lasionectria phormii Lin Zhao, L.W. Hou & Crous, Lasionectriopsis stereicola Lin Zhao & Crous, Nectriopsis cribrariae Lin Zhao & Crous, Nectriopsis floccosa Lin Zhao & Crous, Ovicillium theobromae Lin Zhao & Crous, Paracylindrocarpon jigongshanense Lin Zhao & Crous, Paracylindrocarpon spartinae Lin Zhao & Crous, Parageonectria arachispora Lin Zhao & Crous, Paragliomastix venezuelana Lin Zhao & Crous, Physaromyces sterilis Lin Zhao & Crous, Protocreopsis chlamydospora Lin Zhao & Crous, Protocreopsis gallica Lin Zhao & Crous, Roumegueriella echinulata Lin Zhao & Crous, Sesquicillium pouteriae Lin Zhao & Crous, Sesquicillium thailandense Lin Zhao & Crous, Smyrniomyces setaceus Lin Zhao & P.W. Crous. New combinations: Clavatomyces korfii (Lechat & J. Fourn.) Lin Zhao & Crous, Vitreipilata cirsii (Lechat & J. Fourn) Lin Zhao & Crous, Protocreopsis loweniae (Flakus et al.) Lin Zhao & Crous, Protocreopsis vulpina (Cooke) Lin Zhao & Crous, Proxiovicillium capsici (S.Q. Tong & Y.J. Wu) Lin Zhao & Crous, Sesquicillium shanghaiense (Zhang et al.) Lin Zhao & Crous, Urticomyces pseudoarenulus (Lechat & J. Fourn) Lin Zhao & Crous, Verruciconidia guizhouensis (S.Q. Tong & Y.J. Wu) Lin Zhao & Crous, Verruciconidia saulensis (Lechat & J. Fourn.) Lin Zhao & Crous. New synonyms: Clonostachys aquatica D.F. Bao et al., Emericellopsis microspora Backus & Orpurt. Citation: Zhao L, Groenewald JZ, Hou LW, Summerbell RC, Crous PW (2025). Bionectriaceae: a poorly known family of hypocrealean fungi with major commercial potential. Studies in Mycology 111: 115-198. doi: 10.3114/sim.2025.111.04.
- Research Article
1
- 10.3114/sim.2025.110.02
- Mar 1, 2025
- Studies in mycology
- M Z Wang + 15 more
The order Chaetothyriales comprises the black yeasts and relatives, of which numerous species are prevalent as opportunists on human hosts. The present paper introduces a clade of species that live in ant nests inside hollow structures of tropical plants (so-called domatia) and their closest relatives. To clarify the evolutionary trajectory of the domatia-associated clade, molecular, morphological, and physiological data were analysed. The position of the domatia clade within the Chaetothyriales was assessed by phylogenetic analysis of ITS and LSU. Species delimitations were calculated and genealogical concordance performed with a dataset including the gene of the ribosomal operon, β-tubulin (BT2) and RNA polymerase II largest subunit (RBP1). Genome sequencing allowed additional analysis of mating types, mitochondrial genomes, and estimation of a species tree based on the proteins of 770 single copy orthologous genes. A new family with two new genera in Chaetothyriales was introduced to accommodate the taxa from ant-inhabited domatia and a related clade of plant- and rock-colonizing species. The family is monophyletic and has strong statistical support. Although species delimitation criteria suggested the separation of more than 10 species in the domatia-clade, genealogical concordance of ribosomal and housekeeping gene markers indicated genetic exchange. Seven new species were delineated, with species also being characterized by phenotypic features of fungal colony morphology, micromorphology, physiology and ecology. However, intra-specific variability remained exceptionally large and did not always match with ecological and geographic data. It is hypothesized that the high degrees of intra- and interspecific variability of some of the clades acknowledged as separate species might be related to extended periods of molecular evolution. The newly described species seem to have their preferred habitat in tropical ant nests, and they have adapted to this specific environment. Ant-domatia provide a remarkable habitat rich in volatile chemicals, which could be tolerated by the fungi under study. The family is distantly related to the family Herpotrichiellaceae comprising numerous human-opportunistic species, where hydrocarbon tolerance has been hypothesized to play a role in black yeast evolution. Taxonomic novelties: New family: Domatiomycetaceae Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog. New genera: Domatiomyces Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Lapsomyces Meizhu Wang, S.A. Ahmed & de Hoog. New species: Domatiomyces globalis Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Domatiomyces clavatus Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Domatiomyces catenatus Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Domatiomyces disarticulatus Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Domatiomyces pauciseptatus Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Domatiomyces germinans Meizhu Wang, Voglmayr, V.E. Mayer, S.A. Ahmed & de Hoog, Lapsomyces furvus Meizhu Wang, S.A. Ahmed & de Hoog. New combinations: Lapsomyces behniae (Crous) Meizhu Wang, S.A. Ahmed & de Hoog, Lapsomyces hostae (Crous) Meizhu Wang, S.A. Ahmed & de Hoog, Lapsomyces scillae (Deighton) Meizhu Wang, S.A. Ahmed & de Hoog. Citation: Wang MZ, Belmonte-Lopes R, Pan T, Ahmed SA, Rodrigues Lustosa BP, Quan Y, Al-Hatmi AMS, Mayer VE, Voglmayr H, Grisolia ME, de Souza Lima BBJF, Vicente VA, Zhou SQ, Cao Y, Kang YQ, de Hoog GS (2025). A new family of ant-associated fungi in Chaetothyriales. Studies in Mycology 110: 111-143. doi: 10.3114/sim.2024.110.02.
- Research Article
- 10.3114/sim.2024.110.02
- Jan 1, 2025
- Studies in Mycology
- M.z Wang + 15 more
The order Chaetothyriales comprises the black yeasts and relatives, of which numerous species are prevalent as opportunists on human hosts. The present paper introduces a clade of species that live in ant nests inside hollow structures of tropical plants (so-called domatia) and their closest relatives. To clarify the evolutionary trajectory of the domatia-associated clade, molecular, morphological, and physiological data were analysed. The position of the domatia clade within the Chaetothyriales was assessed by phylogenetic analysis of ITS and LSU. Species delimitations were calculated and genealogical concordance performed with a dataset including the gene of the ribosomal operon, β-tubulin (BT2) and RNA polymerase II largest subunit (RBP1). Genome sequencing allowed additional analysis of mating types, mitochondrial genomes, and estimation of a species tree based on the proteins of 770 single copy orthologous genes. A new family with two new genera in Chaetothyriales was introduced to accommodate the taxa from ant-inhabited domatia and a related clade of plant- and rock-colonizing species. The family is monophyletic and has strong statistical support. Although species delimitation criteria suggested the separation of more than 10 species in the domatia-clade, genealogical concordance of ribosomal and housekeeping gene markers indicated genetic exchange. Seven new species were delineated, with species also being characterized by phenotypic features of fungal colony morphology, micromorphology, physiology and ecology. However, intra-specific variability remained exceptionally large and did not always match with ecological and geographic data. It is hypothesized that the high degrees of intra- and interspecific variability of some of the clades acknowledged as separate species might be related to extended periods of molecular evolution. The newly described species seem to have their preferred habitat in tropical ant nests, and they have adapted to this specific environment. Ant-domatia provide a remarkable habitat rich in volatile chemicals, which could be tolerated by the fungi under study. The family is distantly related to the family Herpotrichiellaceae comprising numerous human-opportunistic species, where hydrocarbon tolerance has been hypothesized to play a role in black yeast evolution.
- Research Article
- 10.3114/sim.2025.111.04_supp
- Jan 1, 2025
- Studies in Mycology
Fig. S1. Phylogenetic tree inferred from a Maximum Likelihood (RAxML) analysis based on a concatenated alignment of ITS, and LSU sequences of 706 strains representing Bionectriaceae and outgroups. Numbers at branches indicate support values (RAxML-BS) above 50 %. The new species are printed in red font and new combinations in blue font and the ingroup genera highlighted with coloured boxes. Strains with a type status are indicated with “T”. The tree is rooted to Bullanockia australis (CBS 142093), Flammocladiella aceris (CBS 138906), F. anomiae (CBS 142775), F. decora (CBS 142776), Stromatonectria caraganae (CBS 125579, CBS 127387), Tilachlidium brachiatum (CBS 505.67, CBS 363.97) and Xanthonectria pseudopeziza (CBS 140160, CBS 141245). The scale bar represents the expected number of changes per site. <br />Fig. S2. Phylogenetic tree inferred from a Maximum Likelihood (RAxML) analysis based on a concatenated alignment of ITS, LSU, RPB2, and TEF1 sequences of 751 strains representing Bionectriaceae and allied families in Hypocreales and outgroups. Numbers at branches indicate support values (RAxML-BS) above 50 %. The new species are printed in red font and new combinations in blue font and the ingroup genera highlighted with coloured boxes. Strains with a type status are indicated with “T”. The tree is rooted to Paracremonium inflatum (CBS 485.77), Sarocladium oryzae (CBS 180.74), S. zeae (CBS 800.69), and Xenoacremonium recifei (CBS 137.35). The scale bar represents the expected number of changes per site. <br />Table S1. Strains used in this study with details of their host, location, and GenBank accessions numbers.
- Research Article
3
- 10.3114/sim.2025.112.02
- Jan 1, 2025
- Studies in mycology
- B.s Weir + 22 more
Facial eczema (FE) in ruminants is associated with the fungal toxin sporidesmin that can cause significant mortality in grazing livestock. Incidences are particularly severe in New Zealand but are reported worldwide. The syndrome has historically been attributed to Pithomyces chartarum, a species transferred to Pseudopithomyces in 2015, but the classification of many other Pithomyces species remains unresolved. In this study we investigated the taxonomy of Pseudopithomyces using modern species concepts and clarified which species make sporidesmin. Fungal isolates were cultured from grass samples obtained from New Zealand farms and roadside collections in 2014-2022. International isolates, including all available types, and historic isolates deposited in the International Collection of Microorganisms from Plants (ICMP) were also evaluated. Phylogenetic analyses of the ITS region plus four concatenated protein coding genes distinguished 15 species in the genus. We describe Pseudopithomyces toxicarius sp. nov. as a novel sporidesmin producing species, most formerly identified as Pse. chartarum, with 80 % of isolates in this study able to produce the toxin. Two Pithomyces species are combined into Pseudopithomyces as Pseudopithomyces cynodontis comb. nov. and Pseudopithomyces pavgii comb. nov. We also place Pseudopithomyces pandanicola in synonymy with Pseudopithomyces palmicola. Pithomyces terricola is reclassified into the family Longipedicellataceae as Pseudoxylomyces terricola comb. nov. Pseudopithomyces chartarum was the only other species where sporidesmin was detected, but this was found in only one of 14 isolates we tested. The extent of sporidesmin synthesis in this genus remains to be determined due to the limited availability of strains for testing in other species. Analysis of single nucleotide polymorphisms from whole genome Illumina sequences of isolates from Pse. toxicarius, Pse. chartarum and Pse. palmicola revealed distinct genetic subclades within each species. Four species were detected in New Zealand. Pseudopithomyces toxicarius and Pse. chartarum were recovered from grass samples collected from the North and South Islands, Pse. palmicola ICMP 12878 was recovered once from pasture at a North Island research station in 1993, and Pseudopithomyces sp. 'gladiolus NZ', which is currently undescribed. No species were unique to New Zealand, suggesting widespread global distribution. Taxonomic novelties: New species: Pseudopithomyces toxicarius B.S. Weir, D. Lee, J.S. Sidhu, & C.R. Voisey. New combinations: Pseudopithomyces cynodontis (M.B. Ellis) B.S. Weir & D. Lee, Pseudopithomyces pavgii (V.R. Nath) B.S. Weir & D. Lee, Pseudoxylomyces terricola (Manohar. & P. Rama Rao) B.S. Weir & D. Lee. Citation: Weir BS, Sidhu JS, Brosnahan CL, Lee D, Maclean PH, Park D, Jauregui R, Johnson RD, Petterson ME, Williams AFR, Morse NR, Sprosen JM, Lim Y-W, Bridgeman BJ, Walker TJ, Kumar S, Mace WJ, Prakash S, Liu X, Hume DE, Couldrey C, Beever RE, Voisey CR (2025). Global diversity analysis of plant-associated Pseudopithomyces fungi reveals a new species producing the toxin associated with facial eczema in livestock: Pseudopithomyces toxicarius sp. nov. Studies in Mycology 112: 39-73. doi: 10.3114/sim.2025.112.02.
- Research Article
- 10.3114/sim.2025.112.03
- Jan 1, 2025
- Studies in mycology
- D.p Overy + 11 more
Polar, high altitude montane and cold desert environments harbour only sparse plant life and often remain frozen for extended periods. Because of their remoteness, often combined with restricted access, such regions are rarely visited and the fungal biodiversity of the soils is scarcely studied. Despite this, when such studies are undertaken, psychrophilic Penicillium species are often reported and the isolates exhibit a high spectrum of biologically active compounds of biotechnological interest. Small molecule profiling by mass spectrometry (often called 'metabolomics') can supplement phylogenetic species concepts and provide information to characterize variation within species or populations. During large scale fungal isolation surveys exploring new psychrophilic fungi from high altitude alpine and arctic tundra soils, several undescribed Penicillium species were discovered. A polyphasic taxonomic approach was adopted to formally describe ten new species using multigene phylogenetic analyses and phenotypic characterizations including secondary metabolite production, colony characters, and microscopic analysis of morphological structures. Using untargeted metabolomics and molecular networking tools, an emphasis was made to characterize, compare and discuss in depth, the chemical diversity associated with these new Penicillium species. Taxonomic novelties: New species: Penicillium algidum Visagie, Overy, Seifert & Frisvad, Penicillium aquamarinum Visagie, Overy, Seifert & Frisvad, Penicillium discoense Visagie, Overy, Seifert & Frisvad, Penicillium hesseltinei Visagie, Overy, Seifert & Frisvad, Penicillium jugorum Visagie, Overy, Seifert & Frisvad, Penicillium marthae Visagie, Overy, Seifert & Frisvad, Penicillium oreophilum Visagie, Overy, Seifert, Christensen & Frisvad, Penicillium rivulorum Visagie, Overy, Seifert & Frisvad, Penicillium turcosum Visagie, Overy, Seifert & Frisvad, Penicillium wyomingense Visagie, Overy, Seifert & Frisvad. Citation: Overy DP, Frisvad JC, Witte TE, Hicks CL, Hermans A, Sproule A, Louis-Seize G, Seifert KA, Yilmaz N, Price J, van Vuuren NI, Visagie CM (2025). Chemodiversity of Penicillium isolated from alpine and arctic environments, including ten new species. Studies in Mycology 112: 75-116. doi: 10.3114/sim.2025.112.03.